A standard pickup-type machining apparatus has a frame on which a vertically shiftable spindle carrying a workpiece grab is rotatable. A machining station is provided in the frame below the spindle, and a transfer station below the machining station. A workpiece holder, which can be a turret holding a number of tools, is horizontally shiftable toward and away from the machining station, and a conveyor extends horizontally into and even through the transfer station.
In a typical machining cycle the conveyor transports an unmachined workpiece horizontally into the transfer station. Then the spindle drops, engages the unmachined workpiece with the grab, then raises the workpiece to the machining station, and then holds the workpiece in the machining station. The tool is brought horizontally into engagement with the workpiece, either while the workpiece is stationary to, for instance, bore a hole in it, or while it is rotating to machine or finish its outer surface. When at least one such machining operation is completed, the tool is withdrawn horizontally away from the workpiece, any rotation of the workpiece is stopped, and the spindle is lowered and the grab released to set the workpiece down on the conveyor in the transfer station, whereupon the machined workpiece is transported away and the cycle can be repeated.
In EP 1 711 309 two workpiece spindles are provided and two turrets. The machine operates by way of a pendulum mechanism so that while one spindle processes a workpiece, the other can be loaded. Four numerically controlled axes are provided and the loading takes place using two loading and unloading devices.